Additional firepower is a primary reason for Everton's improvement under their new manager.

While their defence has maintained one of the best records in the division, there has been an obvious upgrade in attack, bridging the gap to the Premier League's top four.

Last season, the Toffees scored 17 goals fewer than any Champions League side, finishing 10 points off the pace. With Lukaku on board, suddenly Everton are one point behind, scoring just five goals fewer than fourth-placed Arsenal.

A look at Everton's return with and without the Belgian not only emphasises his value but also suggests his presence throughout the season would have secured a top-four finish, such is the clear difference he makes.

Everton With/Without Lukaku

With Lukaku

Without Lukaku

Last Season

Games

28

7

38

Goals

52

5

55

Goals per game

1.9

0.7

1.4

Wins

18

2

16

Win percentage

64%

29%

42%

Points per game

2.1

1.3

1.7

WhoScored.com

Everton did not score in four of the seven games without Lukaku, unable to find the net altogether against Cardiff, West Brom, Chelsea and Tottenham. Had the striker featured in those games, the Toffees would almost certainly be above Arsenal right now.

So what of Lukaku's qualities?

Alex Livesey/Getty Images

Only five players found the net more during last season and, despite an injury in January, only eight players have more goals this current campaign.

At this primitive stage of his career, he has already proved himself as one of the Premier League's leading marksmen, something few other transfer targets have done.

Lukaku's goals have been key this season, winning 12 points on their own. After his strike against Arsenal, only Luis Suarez (13) and Daniel Sturridge (18) had been more valuable to their respective sides in terms of points.

In total, his 13 Premier League strikes, coupled with six assists, account for exactly a third of the Toffees' goals—one of the best proportions in England.

Lukaku's early form at Everton even distinguished him as one of the Premier League's all-time most clinical finishers:

117 - Romelu Lukaku has the best minutes per goal rate in Premier League history (minimum 20 goals). Prolific.

Adding a genuine goal threat has finally enabled the Toffees to pick up points without finding top gear, something they had struggled to do for several seasons.

Lukaku's presence has allowed them to play poorly and win, a key trait for any top side.

Julian Finney/Getty Images

In terms of attributes, athletically he's a manager's dream, as fast and as strong as any leading striker.

His movement is also exceptional and something Everton haven't always capitalised upon this season, with attacking midfielders often missing a chance to play him through.

Alex Livesey/Getty Images

Whether he's in scoring form or not, Lukaku attracts attention and occupies defenders, freeing up space for others.

There are obviously areas that can be improved, such as his touch and link-up play, but the key point to remember is that he's still only 20 and nowhere near the finished product.

Scarily, everything on display so far is just his potential, which also fits in with Everton's need of buying sell-on value.

Other targets, such as Wilfried Bony, via the Mirror, may contribute similar returns to Lukaku but have far less room to develop. While he would cost a similar fee and perhaps contribute a similar return, Bony is 25, meaning his value would diminish after a couple of years at the club.

Lukaku vs. Bony

Lukaku

Bony

Games

28

31

Minutes

2293

2202

Goals

13

13

Shots

88

99

Shot Accuracy

63%

43%

Chance Conversion

20%

16%

Chances Created

31

23

Assists

6

3

Squawka.com

Comparing both strikers suggests a similar production, albeit with the Belgian edging most departments. The fact Lukaku is five years younger than Bony and has more room to grow makes him a far better option.

For Everton to spend lavishly, it must be on players who seem certain to improve.

Is signing Lukaku the Toffees' No. 1 priority this summer?

YesNoSubmit Votevote to see results

Is signing Lukaku the Toffees' No. 1 priority this summer?

Yes

93.9%

No

6.1%

Total votes: 759

With a few seasons of Lukaku, the Toffees could have a £30 million striker on their hands, an ideal scenario for their limited resources.

As the earlier statistics show, Lukaku is already a top-four-calibre striker. With him in the team, Everton have been a top-four team, and adding him on a permanent basis would strengthen their challenge for next season.

Where the Toffees may ultimately fall short this year is because of their return in the seven games without Lukaku, hurt by their lack of depth behind him.

Clearly, his goals have been integral, and finding a solution up front is Everton's most pressing need for next season.

If Chelsea make him available, Lukaku is the best option—but he shouldn't be the only striker to arrive at Goodison Park.